Browse
Submit Data
Databases
API
Help

Dataset Information

15 Views

0 Connections

0 Citations

0 Reanalyses

0 Downloads

Omics score: 0

Diastereoselective Pt catalyzed cycloisomerization of polyenes to polycycles.

ABSTRACT: Application of a tridentate NHC containing pincer ligand to Pt catalyzed cascade cyclization reactions has allowed for the catalytic, diastereoselective cycloisomerization of biogenic alkene terminated substrates to the their polycyclic counterparts.

SUBMITTER: Geier MJ

PROVIDER: S-EPMC3985707 | biostudies-literature | 2014 Feb

REPOSITORIES: biostudies-literature

ACCESS DATA

Json Xml

Publications

Diastereoselective Pt catalyzed cycloisomerization of polyenes to polycycles.

Geier Michael J MJ Gagné Michel R MR

Journal of the American Chemical Society 20140213 8

Application of a tridentate NHC containing pincer ligand to Pt catalyzed cascade cyclization reactions has allowed for the catalytic, diastereoselective cycloisomerization of biogenic alkene terminated substrates to the their polycyclic counterparts. ...[more]

PMID: 24517454

Similar Datasets

Gold-catalyzed diastereoselective cycloisomerization of alkylidene-cyclopropane-bearing 1,6-diynes.

Project description:An unprecedented gold-catalyzed diastereoselective cycloisomerization of 1,6-diynes bearing an alkylidene cyclopropane moiety has been developed. This methodology enables rapid access to a variety of 1,2-trimethylenenorbornanes, which are important building blocks in the preparations of abiotic and sesquiterpene core structures.

| S-EPMC4120096 | biostudies-literature

Enantioselective, Lewis Base-Catalyzed Sulfenocyclization of Polyenes.

Project description:A sulfenium-ion-initiated, catalytic, enantioselective polyene cyclization is described. Homogeranylarenes and ortho-geranylphenols undergo polycyclization in good yield, diastereoselectivity, and enantioselectivity. The stereodetermining step is the generation of an enantiomerically enriched thiiranium ion from a terminal alkene and a sulfenylating agent in the presence of a chiral Lewis basic catalyst. The use of hexafluoroisopropyl alcohol as the solvent is crucial to obtain good yields. The thioether moiety resulting from the reaction can be subsequently transformed into diverse oxygen and carbon functionality postcyclization. The utility of this method is demonstrated by the enantioselective syntheses of (+)-ferruginol and (+)-hinokiol.

| S-EPMC6008787 | biostudies-literature

Electronic effects in the pt-catalyzed cycloisomerization of propargylic esters: synthesis of 2,3-disubstituted indolizines as a mechanistic probe.

Project description:The initial 5-exo versus 6-endo cyclization of the acyl group onto the activated alkyne of propargylic esters has been found to be dependent on electronic effects of the acyl, alkyne, and propargylic carbon substituents. These electronic effects control the ratio of 2,3-disubstituted versus 1,3-disubstituted indolizine products formed when substrates bearing pyridines at the alkyne terminus are used.

| S-EPMC3342703 | biostudies-literature

Computational Studies on the Pt(II)-Catalyzed Cycloisomerization of 1,6-dienes into Bicyclopropanes: A Mechanistic Quandary Evaluated by DFT.

Project description:The mechanism of the (bis(phosphanylethyl)phosphane)Pt(2+) catalyzed cyclo-isomerization reaction of 7-methyl-octa-1,6-diene to form 1-isopropylbicyclo[3.1.0]hexane was studied using computational methods. The cyclopropanation step was found to be the turnover-limiting step. The overall reaction proceeds via both a 5-exo and a 6-endo route. W conformations were shown to facilitate cyclopropanation, but do not have any influence on the rate of the 1,2-hydride shifts.

| S-EPMC2700740 | biostudies-literature

Computational ligand design in enantio- and diastereoselective ynamide [5+2] cycloisomerization.

Project description:Transition metals can catalyse the stereoselective synthesis of cyclic organic molecules in a highly atom-efficient process called cycloisomerization. Many diastereoselective (substrate stereocontrol), and enantioselective (catalyst stereocontrol) cycloisomerizations have been developed. However, asymmetric cycloisomerizations where a chiral catalyst specifies the stereochemical outcome of the cyclization of a single enantiomer substrate--regardless of its inherent preference--are unknown. Here we show how a combined theoretical and experimental approach enables the design of a highly reactive rhodium catalyst for the stereoselective cycloisomerization of ynamide-vinylcyclopropanes to [5.3.0]-azabicycles. We first establish highly diastereoselective cycloisomerizations using an achiral catalyst, and then explore phosphoramidite-complexed rhodium catalysts in the enantioselective variant, where theoretical investigations uncover an unexpected reaction pathway in which the electronic structure of the phosphoramidite dramatically influences reaction rate and enantioselectivity. A marked enhancement of both is observed using the optimal theory-designed ligand, which enables double stereodifferentiating cycloisomerizations in both matched and mismatched catalyst-substrate settings.

| S-EPMC4728367 | biostudies-literature

Rh(I)-Catalyzed Cycloisomerization of 1,6-Enynes.

Project description:A new and unexpected Rh(I)-catalyzed cycloisomerization of 1,6-enynes is reported. Several different alkyne substitution patterns were evaluated under the reaction conditions, including a deuterated derivative that provides some insight into the reaction mechanism.

| S-EPMC4655000 | biostudies-literature

Gold-Catalyzed Cycloisomerization of Sulfur Ylides to Dihydrobenzothiepines.

Project description:The metal-promoted nucleophilic addition of sulfur ylides to π-systems is a well-established reactivity. However, the driving force of such transformations, elimination of a sulfide moiety, entails stoichiometric byproducts making them unfavorable in terms of atom economy. In this work, a new take on sulfur ylide chemistry is reported, an atom-economical gold(I)-catalyzed synthesis of dihydrobenzo[b]thiepines. The reaction proceeds under mild conditions at room temperature.

| S-EPMC7496544 | biostudies-literature

Palladium-catalyzed 1,4-difunctionalization of butadiene to form skipped polyenes.

Project description:A palladium-catalyzed 1,4-addition across the commodity chemical 1,3-butadiene to afford skipped polyene products is reported. Through a palladium ? ? ? ? ? allyl isomerization, two new carbon-carbon bonds are formed with high regioselectivity and trans stereoselectivity of the newly formed alkene. The utility of this method is highlighted by the successful synthesis of the ripostatin A skipped triene core.

| S-EPMC3688275 | biostudies-literature

Base-catalyzed diastereoselective trimerization of trifluoroacetone.

Project description:Amphiphilic fluorocarbons have unique properties that facilitate their self assembly and adhesion to both inorganic and biological substrates. Incorporation of these moieties into valuable constructs typically require complex synthetic routes that have limited their use. Here, the base-catalyzed diastereoselective synthesis of 6-methyl-2,4,6-tris(trifluoromethyl)tetrahydro-2H-pyran-2,4-diol is reported. Trimerization of trifluoroacetone in the presence of 5 mol% KHMDS delivers one of four diastereomers selectively in 81% yield with no column chromatography. Temperature screening revealed the reversibility of this trimerization and the funneling of material into the most thermodynamically stable oxane. Subsequent functionalization with boronic acids is reported.

| S-EPMC5584686 | biostudies-literature

Zirconocene catalyzed diastereoselective carbometalation of cyclobutenes.

Project description:The regio- and diastereoselective zirconocene-catalyzed carbomagnesiation of cyclobutenes is herein reported to afford configurationally stable cyclobutylmagnesium species that could subsequently react with a large variety of electrophiles to give polysubstituted cyclobutane species as a single diastereoisomer.

| S-EPMC5365058 | biostudies-literature

OmicsDI is part of the ELIXIR infrastructure

OmicsDI is an Elixir interoperability service. Learn more ›

OmicsDI Databases

PRIDE
PeptideAtlas
MassIVE
JPOST Repository
Physiome Model Repository

EGA
EVA
ENA
LINCS
PAXDB
Cell Collective

MetaboLights
Metabolomics Workbench
MetabolomeExpress
GNPS
BioModels
FAIRDOMHub

ArrayExpress
dbGaP
ExpressionAtlas
GEO
NODE

Information

Databases
Help
API
Contact us
Code on GitHub
Terms of use
Submit Data